P.R. Laws tit. 31, § 3061
2019-02-20 00:00:00+00
Obligations, the fulfillment of which has been fixed for a day certain, shall only be demandable when the proper day arrives.
A day certain is understood to be one which must necessarily arrive, even though its date be unknown.
If the uncertainty should consist in the arrival or nonarrival of the day, the obligation is conditional and shall be governed by the rules of §§ 3041-3052 of this title.
History —Civil Code, 1930, § 1078.